1. Field of the Invention
Exemplary embodiments of the invention are directed to a nasal ventilation interface adaptable to be connected to a source of ventilation.
2. Discussion of Related Art
Obstructive sleep apnea syndrome (commonly referred to as obstructive sleep apnea, sleep apnea syndrome, and/or sleep apnea) is a medical condition which includes repeated, prolonged episodes of cessation of breathing during sleep. During a period of wakefulness, the muscles of the upper part of the throat passage of an individual keep the passage open, thereby permitting an adequate amount of oxygen to flow into the lungs. During sleep, the throat passage tends to narrow due to the relaxation of the muscles. In those individuals having a relatively normally sized throat passage, the narrowed throat passage remains open enough to continue to permit the adequate amount of oxygen to flow into the lungs. However, in those individuals having a relatively smaller sized throat passage, the narrowed throat passage prohibits the adequate amount of oxygen from flowing into the lungs. Additionally, a nasal obstruction, such as a relatively large tongue, and/or certain shapes of the palate and/or the jaw of the individual further prohibit the adequate amount of oxygen from flowing into the lungs.
The individual having the above-discussed conditions can stop breathing for one or more prolonged periods of time (e.g., 10 seconds or more). The prolonged periods of time during which breathing is stopped, or apneas, are generally followed by sudden reflexive attempts to breathe. The reflexive attempts to breathe are generally accompanied by a change from a relatively deeper stage of sleep to a relatively lighter stage of sleep. As a result, the individual suffering from obstructive sleep apnea syndrome generally experiences fragmented sleep that is not restful. The fragmented sleep results in one or more of excessive and/or inappropriate daytime drowsiness, headache, weight gain or loss, limited attention span, memory loss, poor judgment, personality changes, lethargy, inability to maintain concentration, and/or depression.
Other medical conditions can also prevent individuals, including adults and infants, from receiving the adequate amount of oxygen into the lungs. For example, an infant who is born prematurely can have lungs that are not developed to an extent necessary to receive the adequate amount of oxygen. Further, prior to, during, and/or subsequent to certain medical procedures and/or medical treatments, an individual can be unable to receive the adequate amount of oxygen.
Under these circumstances, it is known to use a ventilation interface to apply a positive pressure to the throat of the individual, thereby permitting the adequate amount of oxygen to flow into the lungs. In the known ventilation interface, oxygen and/or room air containing oxygen is delivered through the mouth and/or nose of the individual. Known types of positive pressure applied by the known ventilation interface include continuous positive airway pressure (CPAP) in which a positive pressure is maintained in the throat passage throughout a respiratory cycle, bi-level positive airway pressure (BiPAP) in which a relatively high positive pressure is maintained during inspiration and a relatively low positive pressure is maintained during expiration, and intermittent mechanical positive pressure ventilation (IPPV) in which a positive pressure is applied when apnea is sensed (i.e., the positive airway pressure is applied intermittently or non-continuously).
One conventional ventilation interface for the application of such positive pressures includes a face mask that covers the nose and/or mouth, as well as a pair of nasal pillows that are inserted into corresponding nares of the naris.
In the conventional art, pressure must be applied between the required harness and the head of the individual to maintain the required seal. As a result, the harness is generally uncomfortable to wear, particularly when sleeping. The applied pressure often results in undesirable irritation and sores caused by movement of the mask and harness during periods of both wakefulness and sleep. Further, the required seal is generally difficult to maintain when the mask and harness is moved. The mask also generally applies an undesirable pressure to the sinus area that is adjacent to the nose, causing the nasal sinus airways to narrow. This causes an increase in the velocity of flow through the upper anatomical airways and a decrease in the lateral pressure against the nasal mucosal walls. Additionally, the tubing may fold undesirably exacerbating the above problem. The above-discussed combination of increased flow velocity and decreased pressure results in the removal of moisture from the mucosal walls during inspiration and may cause an undesirable drying and a burning sensation within the nares. As a result, the individual may remove the mask to alleviate these discomforts, consequently discontinuing the beneficial application of the positive pressure. Additionally the decreased pressure and increased air flow velocity deteriorate the laminar flow between the air input and output portions of the conventional mask.
For these reasons, it is desirable to provide an improved nasal ventilation interface that overcomes one or more of the above-discussed disadvantages.